MUELLER 104-513
Mueller Frost Proof Sillcock Anti-Siphon Valve (Model 104-513) Instruction Manual
Your guide to installation, operation, and maintenance.
1. Product Overview
The Mueller Frost Proof Sillcock Anti-Siphon Valve, Model 104-513, is designed to provide a reliable outdoor water connection while protecting your plumbing system from freezing temperatures and preventing backflow contamination. This valve features a durable metal construction with a chrome exterior finish, ensuring long-lasting performance and resistance to corrosion. Its design allows for easy operation and efficient water flow.

Figure 1: Main view of the Mueller Frost Proof Sillcock Anti-Siphon Valve, showing the red handle and chrome body.
Key features include:
- Frost-Proof Design: Engineered to prevent freezing by allowing water to drain from the valve body when shut off, protecting against burst pipes in cold weather.
- Anti-Siphon Mechanism: Integrates a backflow preventer to protect your potable water supply from contamination due to back-siphonage.
- Durable Construction: Made from high-quality metal with a chrome finish for extended service life.
- Easy Operation: Designed for smooth and reliable water control.

Figure 2: Side view of the sillcock, highlighting the connection points and overall length.
2. Safety Information
Please read and understand all instructions before installation and use. Failure to follow these instructions may result in property damage or personal injury.
- Always turn off the main water supply before beginning any plumbing work.
- Wear appropriate personal protective equipment, such as safety glasses and gloves, during installation.
- Ensure all connections are properly sealed to prevent leaks.
- If you are unsure about any part of the installation process, consult a qualified plumber.
- This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm (Proposition 65 warning).
3. Components
The Mueller Frost Proof Sillcock Anti-Siphon Valve typically includes the following main components:
- Sillcock body (chrome finish)
- Operating handle (red)
- Anti-siphon vacuum breaker cap
- Inlet connection (1/2 In. Copper SWT or 1/2 In. MIP)
- Outlet connection (3/4 In. MHT - Male Hose Thread)
- Mounting flange
4. Installation Instructions
This section outlines the general steps for installing your frost-proof sillcock. Specific plumbing techniques may vary based on your existing system.
Tools and Materials Required:
- Pipe wrench or adjustable wrench
- Pipe cutter (for copper sweat connection)
- Soldering torch and solder (for copper sweat connection)
- Thread sealant tape (PTFE tape) or pipe joint compound (for MIP connection)
- Drill and appropriate drill bits (if creating a new opening)
- Mounting screws
- Safety glasses and gloves
Installation Steps:
- Turn Off Water Supply: Locate your main water shut-off valve and turn off the water supply to your home or the specific line you will be working on. Open a nearby faucet to relieve pressure in the pipes.
- Prepare Mounting Location: Choose a suitable location on an exterior wall, ensuring there is sufficient space inside the wall for the sillcock's shaft to extend past the interior freeze line. Drill a hole through the wall if necessary, large enough to accommodate the sillcock body.
- Connect to Water Line:
- For 1/2 In. Copper SWT (Sweat) Connection: Clean the end of the existing copper pipe and the sillcock's sweat inlet. Apply flux to both surfaces. Insert the copper pipe into the sillcock's inlet and solder the connection using a torch and lead-free solder. Allow to cool completely.
- For 1/2 In. MIP (Male Iron Pipe) Connection: Apply thread sealant tape (PTFE tape) or pipe joint compound to the threads of the existing 1/2 In. FIP (Female Iron Pipe) fitting. Thread the sillcock's 1/2 In. MIP inlet into the FIP fitting. Tighten securely with a pipe wrench, but do not overtighten.
- Position and Secure: Insert the sillcock through the wall opening. Ensure the valve body is angled slightly downwards towards the exterior to facilitate proper drainage when shut off. Secure the mounting flange to the exterior wall using appropriate screws.
- Check for Leaks: Slowly turn the main water supply back on. Inspect all connections for any signs of leaks. If leaks are detected, turn off the water supply and re-tighten or re-seal the connections as needed.
5. Operating Instructions
Operating the Mueller Frost Proof Sillcock is straightforward:
- To Open: Turn the red handle counter-clockwise until water flows from the spout.
- To Close: Turn the red handle clockwise until the water flow stops completely. Ensure it is fully closed to allow the frost-proof mechanism to function correctly.
Important for Frost Protection: For the frost-proof feature to work effectively, ensure that any hose connected to the sillcock is removed before freezing temperatures occur. This allows the water inside the valve body to drain out, preventing ice formation and potential damage.
6. Maintenance
Regular maintenance helps ensure the longevity and proper function of your sillcock.
- Seasonal Check: Before winter, ensure the sillcock is fully closed and any attached hoses are disconnected. This allows the internal mechanism to drain water and prevent freezing.
- Inspect for Leaks: Periodically check the valve for any drips or leaks from the handle, spout, or wall connection. Address minor leaks promptly by tightening packing nuts or replacing washers if necessary.
- Anti-Siphon Cap: The anti-siphon mechanism contains plastic components that may degrade over time. If you notice water continuously dripping from the anti-siphon cap or if the backflow prevention seems compromised, the cap assembly may need inspection or replacement.
- Cleaning: Clean the exterior of the sillcock with a mild soap and water solution as needed to maintain its chrome finish.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Water drips from the spout when closed. | Valve not fully closed, worn washer/seat, or debris in valve. | Ensure handle is fully tightened. If dripping persists, the internal washer or seat may need replacement. Consult a plumber if uncomfortable with internal repairs. |
| Water leaks from the handle stem. | Loose packing nut or worn packing. | Gently tighten the packing nut behind the handle. If leaking continues, the packing may need to be replaced. |
| Water leaks from the anti-siphon cap. | Damaged or worn anti-siphon components (often plastic). | The anti-siphon vacuum breaker assembly may need to be replaced. Contact Mueller for replacement parts or consult a plumber. |
| No water flow or low water pressure. | Main water supply off, valve not fully open, or obstruction. | Check if the main water supply is on. Ensure the sillcock handle is fully open. Check for any blockages in the hose or spout. |
| Sillcock freezes in cold weather despite being frost-proof. | Hose left attached, improper installation angle, or extreme cold. | Always remove hoses before freezing temperatures. Verify the sillcock is installed with a slight downward slope to allow drainage. In extreme conditions, additional insulation may be required. |
8. Specifications
| Model Number | 104-513 |
| Brand | MUELLER |
| Size | 1/2 In. SWT & 1/2 In. MPT x 3/4 In. MHT |
| Material | Metal |
| Color | Chrome |
| Exterior Finish | Chrome |
| Connector Type | Sweat (Copper SWT) or Male Pipe Thread (MIP) |
| Thread Type (Outlet) | MHT (Male Hose Thread) |
| Item Dimensions (L x W x H) | 3 x 3 x 11.5 inches |
| Item Weight | 1.3 Pounds |
| Manufacturer | Mueller Streamline Company |
| UPC | 032888045132 |
9. Warranty and Support
For specific warranty information regarding your Mueller Frost Proof Sillcock Anti-Siphon Valve, please refer to the documentation included with your purchase or contact Mueller Streamline Company directly. Warranty terms typically cover manufacturing defects under normal use.
For technical support, replacement parts, or further inquiries, please visit the official Mueller website or contact their customer service department. You can also find more information about Mueller products on their Amazon Brand Store.
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